the visible of a stack

J. Landman Gay jacque at hyperactivesw.com
Wed Sep 24 17:27:46 EDT 2008


Mikey wrote:
> Eric,
> Just in case this matters, the stack is a substack.  I open RR, and
> open the mainstack.
> 
> RR is the only application running.
> 
> The stack isn't off-screen.  The loc is the first thing I checked for,
> because I've had situations where stacks migrate to maxint,maxint that
> I haven't figured out.  The msg seems to be the most frequent
> offender.
> 
> The loc of the stack is where I would expect it to be.
> The visible of the stack is true
> I can't see the stack.

The visible property is persistent, like a stack's name, and the engine 
will return the correct value when you ask for it. But there is a 
difference between stack you "go" to and stacks that are loaded into RAM 
but not yet opened. This can happen a couple of different ways. A 
substack is loaded into memory at the same time the mainstack is, but 
the substack is not yet in the message path and is never "visibly" 
visible, even though its propert may be set to true. To actually display 
the substack on screen, you have to go there. As Richard pointed out, 
this is rarely necessary if all you want to do is work with a property 
or other content.

Another way that a stack can be loaded in memory but not quite "real" is 
if you retrieve a property or other data from a stack on disk, which 
isn't yet open; for example:

   get the short name of stack "/myFolder/mystack.rev"

This will cause the engine to load the stack into RAM (in order to check 
the property value) but not place it into the message path. Even if the 
stack's visible is true, you won't see it. It's sort of a ghost stack, 
though it does take up RAM and I often put in a line of script to delete 
it when I'm done accessing it.

-- 
Jacqueline Landman Gay         |     jacque at hyperactivesw.com
HyperActive Software           |     http://www.hyperactivesw.com



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